Alice’s Pistachio Tiramisu Bombe

Method

Step 1
Make the sponge. Heat the oven to 200°C/180°C fan/400°F/Gas 6. Whisk together the eggs and sugar in a stand mixer fitted with the whisk, on medium speed for about 5 minutes, until pale, thick and the mixture leaves a ribbon trail when you lift the whisk. Sift over the flour, cornflour and baking powder and fold in using a large metal spoon.

Step 2
Divide the mixture proportionately between the sandwich tins and Swiss roll tin and bake for about 12–13 minutes, until golden brown. Leave to cool for 5 minutes, then turn out onto baking paper and remove the paper from the undersides of the sponges.

Step 3
Cut the rectangular sponge into five or six 9 x 12cm rectangles and arrange around the inside of the pudding basin. Fill any gaps with triangles of sponge. Still using the sponge rectangle, cut a small circle to fit the base of the bowl, ensuring there are no gaps. Brush the sponge all over with coffee. Set aside while you make the mascarpone mixture.

Step 4
For the mascarpone layer, place the gelatine in a bowl with 6 tablespoons of water and set aside. Whisk the egg yolks in a stand mixer until pale. Place the sugar and 45ml of water in a small pan and heat gently until the sugar dissolves, then increase the heat and cook, without stirring, until it reaches 120°C/248°F on a sugar thermometer. Remove the gelatine from the water, shake off the excess and add to the syrup. With the whisk running on medium speed, gradually pour the sugar syrup onto the egg and whisk until it is fluffy and turns cold.

Step 5
Whisk together the mascarpone and rum in a large bowl using a hand-held electric whisk, to stiff peaks. Transfer to a separate bowl and then whisk the cream to stiff peaks. Fold the two creamy mixtures together to combine. Add the egg-yolk mixture and fold together with a metal spoon to a piping consistency. Pour one third of the mixture into the sponge-lined bowl. Top with the 15cm sponge and brush with a little coffee. Chill to set. Place the remaining mascarpone in the piping bag and chill in the fridge while you make the pistachio praline.

Step 6
Blitz the pistachios briefly in a processor so that the pieces are still fairly big. Spread out the nuts onto the small, lined baking tray. Heat the sugar in a pan over a medium heat, without stirring, until it has dissolved, then increase the heat and cook until it turns a golden brown. Pour the caramelised sugar over the pistachios. Leave to cool and set, then blitz again to a fine powder.

Step 7
For the pistachio parfait, place the gelatine in a bowl with 4 tablespoons of cold water and leave to soften. Whisk the cream in a separate small bowl until thick. Set aside.

Step 8
Place the egg yolks and sugar in a further small bowl and place over a pan of simmering water. Using a hand-held electric whisk, whisk the yolks over the heat until the mixture reaches 65°C/149°F on the sugar thermometer. Remove the gelatine from the water, shaking off the excess, and add to the egg-yolk mixture, whisking to dissolve. Fold together the egg-yolk mixture, the pistachio praline and the whipped cream, and add a little green food colouring. Remove the pudding basin from the fridge and pour in the mixture. Top with the 18cm sponge and brush with a little coffee. Chill for at least 30 minutes to set.

Step 9
Make the chocolate mousse. Pour 75ml of the cream into a small pan and heat gently to just below boiling. Remove from the heat and add the coffee and chocolate. Leave for 5 minutes, then stir until smooth. Place the gelatine in a bowl with 4 tablespoons of water and leave to soften until needed.

Step 10
Whisk the remaining cream in a small bowl until thickened. Place the egg yolks and sugar in a small mixing bowl and place over a pan of simmering water. Using a hand-held electric whisk, whisk over the heat until the mixture reaches 65°C/149°F on the sugar thermometer. Remove the gelatine from the water, shaking off the excess, and add to the egg-yolk mixture, whisking to dissolve. Fold together the egg-yolk mixture, chocolate and whipped cream, then remove the pudding basin from the fridge and pour over. Top with the 20cm sponge and brush with more coffee. Chill to set for at least 4 hours.

Step 11
Meanwhile, make the decoration. Melt the chocolate in a small bowl over a pan of gently simmering water. Allow to cool for 10 minutes to a thick, pouring consistency.

Step 12
Pour some of the chocolate into the silicone sphere mould, filling 3 of the hollows. Run a scraper or the flat side of a knife over the top to level off the hemispheres. Then, invert the cling-film covered bowls and drizzle the chocolate over each, allowing it to drip thickly down the sides to create two cupped flower shapes. Chill everything to set, then remove the chocolate cups from the bowls and cling film and pop out the hemispheres.

Step 13
When you’re ready to serve the dessert, invert the pudding bowl onto a serving plate, remove the bowl and peel away the cling-film lining. Pipe the remaining mascarpone mixture all over, then sprinkle with cocoa powder. Place the larger chocolate cup decoration on top, and the smaller cup inside it. Then, place the three hemispheres, flat-sides downwards, in the base of the smaller cup. Dust the decorations with edible gold glitter.